Errors while deploying Dicoogle-on-aws sample in Cloudformation Stack

Hello, I have been trying to setup a GitHub Project Dicoogle on AWS. However while following the documentation steps to deploy the Cloudformation Stack (Step 13), for the ECS stack (dicoogle-ecs-template.yaml), the ALBCertificate's status is indefinitely stuck on Pending Validation. Due to this, the Cloudformation stack fails with timeout error. I had tried increasing the timeout time; however the same issue was present.  So I made some changes in the dicoogle-main-template.yaml to skip that template, and the dicoogle-privatelink-template.yaml, after which the deployment was successfully.

So then, I followed the steps in the documentation, but in step 17 for the DataSync job to transfer the file from S3 bucket to the EFS, the task fails with the following error:

Task failed to access location loc-08aba4e01d52bfceb: x40016: Could not mount subdirectory /images/froms3 on host 10.0.0.111. Please verify that the subdirectory exists and is properly exported in /etc/exports

So I checked in the Access Point in EFS, there it showed that the access point is available  

I then tried mounting this EFS to an EC2 instance to check the directories, I was getting the following error:

Failed to resolve "fs-0e37194f4b368006a.efs.us-east-1.amazonaws.com". Cannot connect to file system mount target ip address 10.0.0.111. Connection to the mount target IP address 10.0.0.111 timeout. Please retry in 5 minutes if the mount target is newly created. Otherwise check your VPC and security group configuration to ensure your file system is reachable via TCP port 2049 from your instance.

I checked the security groups of the EFS, and there the NFS TCP port 2049 is present, and for the EC2 as well it had been attached. 

Requesting you to provide some assistance to setup this project successfully? 

Below are the links referred to setup this project: https://aws.amazon.com/blogs/opensource/running-dicoogle-an-open-source-pacs-solution-on-aws-part-1/

https://aws.amazon.com/blogs/opensource/running-dicoogle-an-open-source-pacs-solution-on-aws-part-2/

https://github.com/aws-samples/dicoogle-on-aws/tree/main/template